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<h1>src/qvblockprogramming/qvprocessingblocks/qvcannyedgedetector.cpp</h1><a href="qvcannyedgedetector_8cpp.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*</span>
<a name="l00002"></a>00002 <span class="comment"> *      Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012. PARP Research Group.</span>
<a name="l00003"></a>00003 <span class="comment"> *      &lt;http://perception.inf.um.es&gt;</span>
<a name="l00004"></a>00004 <span class="comment"> *      University of Murcia, Spain.</span>
<a name="l00005"></a>00005 <span class="comment"> *</span>
<a name="l00006"></a>00006 <span class="comment"> *      This file is part of the QVision library.</span>
<a name="l00007"></a>00007 <span class="comment"> *</span>
<a name="l00008"></a>00008 <span class="comment"> *      QVision is free software: you can redistribute it and/or modify</span>
<a name="l00009"></a>00009 <span class="comment"> *      it under the terms of the GNU Lesser General Public License as</span>
<a name="l00010"></a>00010 <span class="comment"> *      published by the Free Software Foundation, version 3 of the License.</span>
<a name="l00011"></a>00011 <span class="comment"> *</span>
<a name="l00012"></a>00012 <span class="comment"> *      QVision is distributed in the hope that it will be useful,</span>
<a name="l00013"></a>00013 <span class="comment"> *      but WITHOUT ANY WARRANTY; without even the implied warranty of</span>
<a name="l00014"></a>00014 <span class="comment"> *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the</span>
<a name="l00015"></a>00015 <span class="comment"> *      GNU Lesser General Public License for more details.</span>
<a name="l00016"></a>00016 <span class="comment"> *</span>
<a name="l00017"></a>00017 <span class="comment"> *      You should have received a copy of the GNU Lesser General Public</span>
<a name="l00018"></a>00018 <span class="comment"> *      License along with QVision. If not, see &lt;http://www.gnu.org/licenses/&gt;.</span>
<a name="l00019"></a>00019 <span class="comment"> */</span>
<a name="l00020"></a>00020 
<a name="l00024"></a>00024 
<a name="l00025"></a>00025 <span class="preprocessor">#include &lt;qvip.h&gt;</span>
<a name="l00026"></a>00026 <span class="preprocessor">#include &lt;qvipp.h&gt;</span>
<a name="l00027"></a>00027 <span class="preprocessor">#include &lt;QVPolyline&gt;</span>
<a name="l00028"></a>00028 <span class="preprocessor">#include &lt;QVCannyEdgeDetector&gt;</span>
<a name="l00029"></a>00029 
<a name="l00030"></a>00030 <span class="preprocessor">#ifndef DOXYGEN_IGNORE_THIS</span>
<a name="l00031"></a>00031 <span class="preprocessor"></span>QVCannyEdgeDetector::QVCannyEdgeDetector(QString name): <a class="code" href="classQVProcessingBlock.html" title="Base class for Block threads.">QVProcessingBlock</a>(name)
<a name="l00032"></a>00032         {
<a name="l00033"></a>00033         addProperty&lt;double&gt;(<span class="stringliteral">&quot;cannyHigh&quot;</span>, inputFlag, 150, <span class="stringliteral">&quot;High threshold for Canny operator&quot;</span>, 50, 1000);
<a name="l00034"></a>00034         addProperty&lt;double&gt;(<span class="stringliteral">&quot;cannyLow&quot;</span>, inputFlag, 50, <span class="stringliteral">&quot;Low threshold for Canny operator&quot;</span>, 10, 500);
<a name="l00035"></a>00035         addProperty&lt;bool&gt;(<span class="stringliteral">&quot;applyIPE&quot;</span>, inputFlag, FALSE, <span class="stringliteral">&quot;If we want to apply the IPE algorithm&quot;</span>);
<a name="l00036"></a>00036         addProperty&lt;double&gt;(<span class="stringliteral">&quot;paramIPE&quot;</span>, inputFlag, 5.0, <span class="stringliteral">&quot;IPE parameter (max. allowed distance to line)&quot;</span>, 1.0, 25.0);
<a name="l00037"></a>00037         addProperty&lt;bool&gt;(<span class="stringliteral">&quot;intersectLines&quot;</span>, inputFlag, TRUE, <span class="stringliteral">&quot;If we want IPE to postprocess polyline (intersecting lines)&quot;</span>);
<a name="l00038"></a>00038         addProperty&lt;int&gt;(<span class="stringliteral">&quot;minLengthContour&quot;</span>, inputFlag, 25, <span class="stringliteral">&quot;Minimal length of a contour to be considered&quot;</span>, 1, 150);
<a name="l00039"></a>00039         <span class="comment">//addProperty&lt;int&gt;(&quot;showNothingCannyImage&quot;, inputFlag, 0, &quot;If we want nothing|Canny|original image to be shown&quot;,0,2);</span>
<a name="l00040"></a>00040         <span class="comment">//addProperty&lt;bool&gt;(&quot;showContours&quot;, inputFlag, TRUE, &quot;If we want contours to be shown&quot;);</span>
<a name="l00041"></a>00041 
<a name="l00042"></a>00042         addProperty&lt; QVImage&lt;uChar,1&gt; &gt;(<span class="stringliteral">&quot;Output image&quot;</span>, outputFlag);
<a name="l00043"></a>00043         addProperty&lt; QVImage&lt;uChar,3&gt; &gt;(<span class="stringliteral">&quot;Input image&quot;</span>, inputFlag|outputFlag);
<a name="l00044"></a>00044         addProperty&lt; QList&lt;QVPolyline&gt; &gt;(<span class="stringliteral">&quot;Output contours&quot;</span>, outputFlag);
<a name="l00045"></a>00045         }
<a name="l00046"></a>00046 
<a name="l00047"></a>00047 <span class="keywordtype">void</span> <a class="code" href="classQVCannyEdgeDetector.html#a4ea16e03e6ba5d2dbd69447052999698" title="Function to be defined in subclasses with processing code.">QVCannyEdgeDetector::iterate</a>()
<a name="l00048"></a>00048         {
<a name="l00049"></a>00049         <span class="comment">// 0. Read input parameters</span>
<a name="l00050"></a>00050         <span class="keyword">const</span> <span class="keywordtype">double</span> cannyHigh = getPropertyValue&lt;double&gt;(<span class="stringliteral">&quot;cannyHigh&quot;</span>);
<a name="l00051"></a>00051         <span class="keyword">const</span> <span class="keywordtype">double</span> cannyLow = getPropertyValue&lt;double&gt;(<span class="stringliteral">&quot;cannyLow&quot;</span>);
<a name="l00052"></a>00052         <span class="keyword">const</span> <span class="keywordtype">bool</span> applyIPE = getPropertyValue&lt;bool&gt;(<span class="stringliteral">&quot;applyIPE&quot;</span>);
<a name="l00053"></a>00053         <span class="keyword">const</span> <span class="keywordtype">double</span> paramIPE = getPropertyValue&lt;double&gt;(<span class="stringliteral">&quot;paramIPE&quot;</span>);
<a name="l00054"></a>00054         <span class="keyword">const</span> <span class="keywordtype">bool</span> intersectLines = getPropertyValue&lt;bool&gt;(<span class="stringliteral">&quot;intersectLines&quot;</span>);
<a name="l00055"></a>00055         <span class="keyword">const</span> <span class="keywordtype">int</span> minLengthContour = getPropertyValue&lt;int&gt;(<span class="stringliteral">&quot;minLengthContour&quot;</span>);
<a name="l00056"></a>00056         <span class="comment">//const int showNothingCannyImage = getPropertyValue&lt;int&gt;(&quot;showNothingCannyImage&quot;);</span>
<a name="l00057"></a>00057         <span class="comment">//const bool showContours = getPropertyValue&lt;bool&gt;(&quot;showContours&quot;);</span>
<a name="l00058"></a>00058         <span class="keyword">const</span> <a class="code" href="classQVImage.html">QVImage&lt;uChar,1&gt;</a> image = getPropertyValue&lt; QVImage&lt;uChar,3&gt; &gt;(<span class="stringliteral">&quot;Input image&quot;</span>);
<a name="l00059"></a>00059         <span class="keyword">const</span> uInt cols = image.getCols(), rows = image.getRows();
<a name="l00060"></a>00060 
<a name="l00061"></a>00061         <a class="code" href="classQVImage.html" title="Image representation class for the QVision.">QVImage&lt;sFloat&gt;</a> imageFloat(cols, rows), dX(cols, rows), dY(cols, rows), dXNeg(cols, rows);
<a name="l00062"></a>00062         <a class="code" href="classQVImage.html">QVImage&lt;uChar&gt;</a> canny(cols, rows), buffer;
<a name="l00063"></a>00063 
<a name="l00064"></a>00064         <span class="comment">// 1. Convert image from uChar to sShort</span>
<a name="l00065"></a>00065         Convert(image, imageFloat);
<a name="l00066"></a>00066         <a class="code" href="classQVProcessingBlock.html#a61f390e8790a77175a6d6e1049a9d127" title="Stablish a performance breakpoint in the execution of the block.">timeFlag</a>(<span class="stringliteral">&quot;Convert image from uChar to sShort&quot;</span>);
<a name="l00067"></a>00067 
<a name="l00068"></a>00068         <span class="comment">// 2. Obtain horizontal and vertical gradients from image</span>
<a name="l00069"></a>00069         <a class="code" href="group__qvippFF.html#ga80cdf87494c982146fbaf42fa4e1886f" title="QVision wrapper function for IPP&amp;#39;s ippiFilterSobelHorizMask_32f_C1R.">FilterSobelHorizMask</a>(imageFloat,dY);
<a name="l00070"></a>00070         <a class="code" href="group__qvippFF.html#gac4c214ba6435857ee9874d2103e99418" title="QVision wrapper function for IPP&amp;#39;s ippiFilterSobelVertMask_32f_C1R.">FilterSobelVertMask</a>(imageFloat,dX);
<a name="l00071"></a>00071         <a class="code" href="group__qvippIAALO.html#gadc8a14bd103bb45afa43950ce454f2fd" title="Adds, subtracts, or multiplies pixel values of an image and a constant, and places...">MulC</a>(dX, -1, dXNeg);
<a name="l00072"></a>00072         <a class="code" href="classQVProcessingBlock.html#a61f390e8790a77175a6d6e1049a9d127" title="Stablish a performance breakpoint in the execution of the block.">timeFlag</a>(<span class="stringliteral">&quot;Obtain horizontal and vertical gradients from image&quot;</span>);
<a name="l00073"></a>00073 
<a name="l00074"></a>00074         <span class="comment">// 3. Apply Canny operator</span>
<a name="l00075"></a>00075         <a class="code" href="group__qvippCV.html#ga81da042e746aff629cf0e0f45b0f9cb7" title="Allocates size in a buffer image for temporary data for function Canny.This function...">CannyGetSize</a>(canny, buffer);
<a name="l00076"></a>00076         <a class="code" href="group__qvippCV.html#ga56269a74576283f8743352552aadc12a" title="Creates binary image of source&amp;#39;s image edges, using derivatives of the first...">Canny</a>(dXNeg, dY, canny, cannyLow,cannyHigh, buffer);
<a name="l00077"></a>00077         <a class="code" href="classQVProcessingBlock.html#a61f390e8790a77175a6d6e1049a9d127" title="Stablish a performance breakpoint in the execution of the block.">timeFlag</a>(<span class="stringliteral">&quot;Apply Canny operator&quot;</span>);
<a name="l00078"></a>00078 
<a name="l00079"></a>00079         <span class="comment">// 4. Get contours</span>
<a name="l00080"></a>00080         <span class="keyword">const</span> QList&lt;QVPolyline&gt; contourList = <a class="code" href="group__qvip.html#ga804db01dcec15dce0c303ed4a4715bd6" title="Obtains a list of the 8-connected pixel lines in the imageThis function can be used...">getLineContoursThreshold8Connectivity</a>(canny, 128);
<a name="l00081"></a>00081         <a class="code" href="classQVProcessingBlock.html#a61f390e8790a77175a6d6e1049a9d127" title="Stablish a performance breakpoint in the execution of the block.">timeFlag</a>(<span class="stringliteral">&quot;Get contours&quot;</span>);
<a name="l00082"></a>00082 
<a name="l00083"></a>00083         QList&lt;QVPolyline&gt; outputList;
<a name="l00084"></a>00084         <span class="keywordflow">foreach</span>(<a class="code" href="classQVPolyline.html" title="Polyline representation.">QVPolyline</a> contour,contourList)
<a name="l00085"></a>00085                 <span class="keywordflow">if</span>(contour.size() &gt; minLengthContour)
<a name="l00086"></a>00086                         {
<a name="l00087"></a>00087 <span class="preprocessor">                        #ifdef QVMATRIXALGEBRA_AVAILABLE</span>
<a name="l00088"></a>00088 <span class="preprocessor"></span>                        <span class="keywordflow">if</span>(applyIPE)
<a name="l00089"></a>00089                                 {
<a name="l00090"></a>00090                                 <a class="code" href="classQVPolyline.html" title="Polyline representation.">QVPolyline</a> IPEcontour;
<a name="l00091"></a>00091                                 <a class="code" href="group__qvip.html#ga69b4cc8c2c9561eb4623cb86ddd16fff" title="Eliminates points of a polyline of small shape contribution using the IPE algorithmThis...">IterativePointElimination</a>(contour, IPEcontour, paramIPE, FALSE, intersectLines);
<a name="l00092"></a>00092                                 outputList.append(IPEcontour);
<a name="l00093"></a>00093                                 }
<a name="l00094"></a>00094                         <span class="keywordflow">else</span>
<a name="l00095"></a>00095 <span class="preprocessor">                        #endif // QVMATRIXALGEBRA_AVAILABLE</span>
<a name="l00096"></a>00096 <span class="preprocessor"></span>                                outputList.append(contour);
<a name="l00097"></a>00097                         }
<a name="l00098"></a>00098 
<a name="l00099"></a>00099         <a class="code" href="classQVProcessingBlock.html#a61f390e8790a77175a6d6e1049a9d127" title="Stablish a performance breakpoint in the execution of the block.">timeFlag</a>(<span class="stringliteral">&quot;IPE on contours&quot;</span>);
<a name="l00100"></a>00100 
<a name="l00101"></a>00101         <span class="comment">// 5. Publish resulting data</span>
<a name="l00102"></a>00102         <span class="comment">// Always show Canny image.</span>
<a name="l00103"></a>00103         <span class="comment">//if(showNothingCannyImage == 1)</span>
<a name="l00104"></a>00104         setPropertyValue&lt; QVImage&lt;uChar,1&gt; &gt;(<span class="stringliteral">&quot;Output image&quot;</span>,canny);
<a name="l00105"></a>00105 
<a name="l00106"></a>00106         <span class="comment">//else if(showNothingCannyImage == 2)</span>
<a name="l00107"></a>00107         <span class="comment">//      setPropertyValue&lt; QVImage&lt;uChar,1&gt; &gt;(&quot;Output image&quot;,image);</span>
<a name="l00108"></a>00108         <span class="comment">/*else  {</span>
<a name="l00109"></a>00109 <span class="comment">                QVImage&lt;uChar&gt; whiteImage(cols, rows);</span>
<a name="l00110"></a>00110 <span class="comment">                Set(255, whiteImage);</span>
<a name="l00111"></a>00111 <span class="comment">                setPropertyValue&lt; QVImage&lt;uChar,1&gt; &gt;(&quot;Output image&quot;,whiteImage);</span>
<a name="l00112"></a>00112 <span class="comment">                }*/</span>
<a name="l00113"></a>00113 
<a name="l00114"></a>00114         <span class="comment">//if(showContours)</span>
<a name="l00115"></a>00115         <span class="comment">// Always publish contour list</span>
<a name="l00116"></a>00116         setPropertyValue&lt; QList&lt; QVPolyline&gt; &gt;(<span class="stringliteral">&quot;Output contours&quot;</span>,outputList);
<a name="l00117"></a>00117         <span class="comment">//else</span>
<a name="l00118"></a>00118         <span class="comment">//setPropertyValue&lt; QList&lt; QVPolyline&gt; &gt;(&quot;Output contours&quot;,QList&lt;QVPolyline&gt;());</span>
<a name="l00119"></a>00119 
<a name="l00120"></a>00120         <a class="code" href="classQVProcessingBlock.html#a61f390e8790a77175a6d6e1049a9d127" title="Stablish a performance breakpoint in the execution of the block.">timeFlag</a>(<span class="stringliteral">&quot;Publish results&quot;</span>);
<a name="l00121"></a>00121         }
<a name="l00122"></a>00122 
<a name="l00123"></a>00123 <span class="preprocessor">#endif</span>
</pre></div></div>
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<center><a href="http://perception.inf.um.es/QVision">QVision framework</a>.
<a href="http://perception.inf.um.es">PARP research group</a>.
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